Recently, in the chain block toy used for the above purpose, the male coupling part of the assembly block is connected to the female coupling part of another assembly block in the form of a chain so as to be assembled into various types of structures having a flat or three-dimensional shape, so that the chain block toy may be used as a toy for developing creativity of children.
In such a chain block toy, as shown in FIG. 1, a male coupling part 200 is engaged with a female coupling part through a fitting scheme so as not to be unintentionally separated, while being freely rotatable within a range of 180° in a coupled state. To this end, the male coupling part 200 is formed at an inner center thereof with a guide groove 210, a concave groove 220 is formed at an edge of the male coupling part 200 at a predetermined interval, the female coupling part 100 is formed at an inner center thereof with a guide protrusion 130 fitted to the guide groove 210, and the female coupling part 100 is formed at one side thereof with a stopper protrusion 140 latched to the concave groove 220 to control rotation.
Accordingly, the chain block toy is coupled to be rotatable, and an angle is fixed in a rotated state, so that structures to be assembled may be assembled in various shapes.
Meanwhile, the assembly blocks are used in various forms so as to be assembled into structures having various shapes, and it is possible to assemble various structures by using various assembly blocks such as an assembly block having a male coupling part and a female coupling part, an assembly block having only a plurality of female coupling parts, an assembly block having only a male coupling part, an assembly block formed on both sides thereof with male coupling parts and formed at a center thereof with a plurality of female coupling parts, and an assembly block where a plurality of female coupling parts are provided by lengthening a female coupling part relative to a male coupling part.
In this case, the vertical coupling part 110 has a structure in which vertical supports 110 are vertically positioned and a coupling space 120 to which the male coupling part 200 is fitted is formed between the vertical supports 110. In order to form a plurality of female coupling parts 100, a partition 150 is necessary.
However, since the vertical supports 110 are firmly supported by the partition 150, coupling or decoupling of the male coupling part 200 in the coupling space 120 of the female coupling part 100 is tightly achieved as shown in FIG. 2.
In other words, a force for enabling forced coupling is required when infants or children with weak strength intend to couple the assembly blocks. However, it is very difficult for the infants and children to generate the force for enabling the forced coupling, so that assembly works for the assembly blocks may be very difficult.
In addition, when the assembly block is rotated for angle adjustment in a coupled state, the vertical support 110 firmly supported by the partition 150 generates powder caused by abrasion due to friction, and such abrasion reduces a lifespan of the assembly block, so that the assembly block cannot be used as an assembly block, and it causes hygiene and health problems when the infants or children eat the powder generated by the abrasion.